User

Peripherals

Why can't I see the Registers in a Peripheral?

This is likely caused by the peripheral being powered-off (disabled) in the SYSCTRL register. This is the default state of most peripherals after a reset of the chip.

It is the responsibility of the application to power-on peripherals that it is using (except for those that are permanently powered, such a NVIC and SYSCTRL).

During debug, a peripherals powered state is displayed in various ways:

In the "Peripherals" and "Memory" views the entry for the peripipheral is shaded (light-blue in XP, dark-blue in Vista).

In the "Peripherals" and "Memory" views the tooltip for the peripheral will end with 'Disabled'.

In the SYSCTRL register, the peripherals power bit will be set to RUNMODE_POWEROFF.

During debbug, SYSCTRL can be used to power-on individual peripherals by setting RUNMODE_POWERON in the appropriate peripheral control field:

View the SYSCTL peripheral, by opening the "Peripherals" view, scrolling down to SYSCTRL and checking the checkbox. This will open a view of the SYSCTRL peripheral in the "Memory" window.

In the "SYSCTRL<Peripheral>" Rendering, scroll to the 'RCGCn' register.

Tip: This can be laborious, so you can apply a filter to the view, by right-clicking and selecting 'Add Filter'. Enter 'RCGC' and just the registers beginning with that string are displayed, together with any fields.